This invention relates to an apparatus and method for binding media sheets. More particularly, the invention relates to an apparatus and method for producing a bound document from a plurality of media sheets by individually binding each media sheet to previously bound media sheets.
Current devices and methods for printing and binding media sheets involve printing the desired document on a plurality of media sheets, assembling the media sheets into a stack, and separately stapling, clamping, gluing and/or sewing the stack. In addition to imaging material used to print the document, each of these binding methods require separate binding materials, increasing the cost and complexity of binding. Techniques for binding media sheets using a common printing and binding material are known in the art. These techniques generally involve applying imaging material such as toner to defined binding regions on multiple sheets, assembling the media sheets into a stack, and reactivating the imaging material, causing the media sheets to adhere to one another. These known devices and methods, however, can consume significantly more time than producing an unbound document. Each involves printing the entire or a substantial portion of the desired document, then assembling and aligning the media sheets into a stack in preparation to be bound. Binding the stack of media sheets also entails applying sufficient heat to the binding region to reactivate the imaging material throughout multiple sheets or throughout the entire stack. Consequently, the thickness of the bound document is limited by the device""s ability to adequately heat the binding regions throughout multiple sheets or the stack without damaging the media sheets.
The present invention is directed to a new method and apparatus for binding documents by individually binding each media sheet to previously bound media sheets using imaging material as the binding material. One method embodiment of the invention includes the acts of (1) applying imaging material to a binding region on a single media sheet and activating the imaging material, (2) collecting the sheet together with previously collected sheets in a stack, (3) reactivating the imaging material applied to the binding region of the sheet, and (4) repeating the acts of applying, collecting and reactivating for each sheet in the plurality of sheets to form the finished bound document. One apparatus embodiment of the invention includes a tray for collecting a plurality of media sheets, a heating element near the tray, and a press coupled to the heating element. The heating element is movable between a first position in which the heating element is separated from the media sheets and a second position in which the heating element contacts a media sheet. The press is operative for each sheet output to the tray to press the heating element against the binding region of the sheet to thereby apply pressure and heat to reactivate the imaging material and bind the sheet to the previously bound sheets in the stack.